The 3rd Generation Partnership Project (3GPP), which undertakes activities for standardizing recent mobile communication systems, is in the process of creating specifications for the Evolved Packet System (EPS), which realizes an all-IP architecture (see NPL 1). The EPS is a mobile communication system through which mobile operators and the like provide mobile telephone services, and is structured including a core network called the Evolved Packet Core (EPC), an access network based on the radio communication standard called the Long Term Evolution (LTE), and the like.
Furthermore, in the process of creating specifications for the EPS by the 3GPP, the Network-based IP Flow Mobility (NBIFOM) has been discussed (see NPL 1). The NBIFOM is a technical item that allows one device to simultaneously utilize a 3GPP interface and an interface other than the 3GPP interface (for example, WLAN).
Conventionally, one PDN connection accommodates a communication path or a bearer or a transfer path that passes through any one access network of a 3GPP access network (for example, LTE access network) and an access network other than the 3GPP access network (for example, WLAN access network).
The NBIFOM can maintain a state in which one PDN connection simultaneously accommodates a bearer or communication path or transfer path through the 3GPP access network and a bearer or communication path or transfer path through a network other than the 3GPP access network. Such PDN connection is defined as multi-access PDN connection.
For the NBIFOM, it also has been discussed to stipulate an operation mode indicating an endpoint node that has a leading function for switching a communication path. Specifically, it has been discussed to classify an operation mode into a UE-initiated mode based on a terminal device and a Network-initiated mode based on a network.
A terminal device and each device included in a core network and an access network use an NBIFOM function to be capable of transmitting/receiving data using a communication path through an appropriate access network for each application.
Furthermore, an endpoint node configured to initiate the switching of a flow of the multi-access PDN connection established by using the NBIFOM function can be configured based on the operation mode.